934 resultados para uneven-aged management


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An infinite-horizon discrete time model with multiple size-class structures using a transition matrix is built to assess optimal harvesting schedules in the context of Non-Industrial Private Forest (NIPF) owners. Three model specifications accounting for forest income, financial return on an asset and amenity valuations are considered. Numerical simulations suggest uneven-aged forest management where a rational forest owner adapts her or his forest policy by influencing the regeneration of trees or adjusting consumption dynamics depending on subjective time preference and market return rate dynamics on the financial asset. Moreover she or he does not value significantly non-market benefits captured by amenity valuations relatively to forest income.

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Tutkimuksessa vertailtiin metsän erirakenteisuutta edistävien poimintahakkuiden ja pienaukkohakkuiden kannattavuutta metsänhoitosuositusten mukaiseen metsänkasvatukseen Keski-Suomessa. Poimintahakkuut ja pienaukkohakkuut ovat menetelmiä, joilla voidaan lisätä luonnonmetsän häiriödynamiikan mukaista pienipiirteistä elinympäristöjen vaihtelua ja siksi ne sopivat etenkin erityiskohteisiin monimuotoisuuden, maiseman tai metsien monikäytön vuoksi. Ne johtavat yleensä vähitellen eri-ikäisrakenteiseen metsään, jossa puuston läpimittaluokkajakauma muistuttaa käänteistä J-kirjainta. Eri-ikäisrakenteisen metsänkäsittelyn taloudellista kannattavuutta puoltavat uudistumiskustannusten poisjäänti ja tukkipuihin painottuvat säännöllisin väliajoin toteutuvat hakkuut. Menetelmän soveltumista Suomen olosuhteisiin pidetään kuitenkin epävarmana. Tässä tutkimuksessa tarkasteltiin tasaikäisrakenteisen metsän muuttamista eri-ikäisrakenteiseksi 40 vuoden siirtymäaikana Metsähallituksen hallinnoimassa Isojäven ympäristöarvometsässä Kuhmoisissa. Tutkimusaineisto koostui 405 kuusivaltaisesta tasaikäisestä kuviosta, joiden pinta-alasta metsämaata on 636 hehtaaria. Metsän kehitystä simuloitiin puutason kasvumalleja käyttäen ja käsittelytoimenpiteet simuloitiin viisivuotiskausittain SIMO-metsäsuunnitteluohjelmistolla. Simulointien avulla selvitettiin jokaisen käsittelyskenaarion hakkuumäärät puutavaralajeittain, diskontatut kassavirrat ja puustopääoman muutos tarkasteluajanjakson aikana. Puunkorjuun yksikkökustannusten laskennan apuna käytettiin automatisoitua seurantajärjestelmää, jossa metsäkoneisiin asennettuilla matkapuhelimilla kerättiin MobiDoc2-sovelluksella metsäkoneiden käytöstä kiihtyvyystiedot, GPS-paikkatiedot ja syötetiedot. Lopulta jokaiselle käsittelyskenaariolle laskettiin metsän puuntuotannollista arvoa kuvaavalla tuottoarvon yhtälöllä nettonykyarvot, josta vähennettiin diskontatut puunkorjuun kustannukset. Tutkimuksen tulosten mukaan poimintahakkuun NPV oli 3 prosentin korkokannalla noin 91 % (7420 €/ha) ja pienaukkohakkuiden noin 99 % (8076 €/ha) metsänhoitosuositusten mukaisesta käsittelystä (8176 €/ha). Komparatiivinen statiikka osoitti, että korkokannan kasvattaminen 5 prosenttiin ei olennaisesti lisännyt nettonykyarvojen eroja. Poimintahakkuiden puunkorjuun yksikkökustannukset olivat 0,8 €/m3 harvennushakkuita pienemmät ja 7,2 €/m3 uudistushakkuita suuremmat. Pienaukkohakkuiden yksikkökustannukset olivat 0,7 €/m3 uudistushakkuita suuremmat.Tulosten perusteella on väistämätöntä että siirtymävaihe tasaikäisrakenteisesta eri-ikäisrakenteiseksi metsäksi aiheuttaa taloudellisia tappioita siitäkin huolimatta, että hakkuut ovat voimakkaita ja tehdään varttuneeseen kasvatusmetsään. Tappion määrä on metsän peitteisyyden ylläpidosta aiheutuva vaihtoehtoiskustannus.

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A subset of forest management techniques, termed ecological forestry, have been developed in order to produce timber and maintain the ecological integrity of forest communities through practices that more closely mirror natural disturbance regimes. Even though alternative methods have been described and tested, these approaches still need to be established and analyzed in a variety of geographic regions in order to calibrate and measure effectiveness across different forest types. The primary objective of this research project was to assess whether group selection combined with legacy-tree retention could enhance mid-tolerant tree recruitment in a late-successional northern hardwood forest. In order to evaluate a novel alternative regeneration technique, 49 group-selection openings in three size classes were created in 2003 with a biological legacy tree retained in the center of each opening. Twenty reference sites, managed using single-tree selection, were also analyzed for comparison. The specific goals of the project were to: 1) determine the fate and persistence of the openings and legacy trees 2) assess the understory response of the group-selection openings versus the single-tree selection reference sites, and 3) evaluate the spatial patterns of yellow birch (Betula alleghaniensis Britt.) and eastern hemlock (Tsuga canadensis (L.) Carr.) in the group-selection openings. The results from 8-9 years post-study implementation and the changes that have occurred between 2004/5 and 2011/12 are discussed. The alternative regeneration technique developed and assessed in this study has the potential to enrich biodiversity in a range of forest types. Projected group-selection opening persistence rates ranged from 41-91 years. Openings from 500-1500 m2 are predicted to persist long enough for mid-tolerant tree recruitment. The legacy trees responded well to release and experienced a low mortality rate. Yellow birch (the primary shade mid-tolerant tree in the study area) densities increased with opening size. Maples surpassed all other species in abundance. In the sapling layer, sugar maple (Acer saccharum Marsh.) was 2 to over 300 times more abundant in the group-selection openings and 2 to 3 times more abundant in the references sites than all other species present. Red maple (Acer rubrum L.) was the second most abundant species present in the openings and reference sites. Spatial patterns of yellow birch and eastern hemlock in the openings were mostly aggregated. The southern edges of the largest openings contained the highest magnitude of yellow birch and eastern hemlock per unit area. Continued monitoring and additional treatments will likely be necessary in order to ensure underrepresented species successfully reach maturity.

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Approximately one-fourth of the non-industrial private forestland (NIPF) owners in the state of Michigan, who collectively own approximately 50% of the private forested land, have conducted commercial timber harvest in recent years. Previous studies indicated that NIPFs preferred to manage their forest for a sustained yield of high-quality timber, but were limited to even-aged regeneration treatments or conversion for uneven-aged silviculture due to previous cuttings. Improved knowledge about NIPF’s intentions and forest management behavior could be useful for successful implementation of sustained yield management. This study’s objective was to identify more active NIPF’s attitudes towards timber management, their forest management practices and whether their forest management behavior leads or leads not to q management for sustained yield. Active NIPF’s intentions to harvest timber for biofuels and its suitability with NIPF’s forest management behavior will be discussed. Phone interviews of 30 NIPFs who have experience with commercial timber harvests were conducted between August and October 2011. All interviews were recorded, transcribed, and analyzed for identifying NIPF’s motivations, attitudes, forest management behavior and forestry related knowledge. Interviewees, whether consciously or not, tended to manage their land for a sustained yield and they would be willing to harvest timber for biofuels facility as long as it benefits landowners management goals.

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Forest management not only affects biodiversity but also might alter ecosystem processes mediated by the organisms, i.e. herbivory the removal of plant biomass by plant-eating insects and other arthropod groups. Aiming at revealing general relationships between forest management and herbivory we investigated aboveground arthropod herbivory in 105 plots dominated by European beech in three different regions in Germany in the sun-exposed canopy of mature beech trees and on beech saplings in the understorey. We separately assessed damage by different guilds of herbivores, i.e. chewing, sucking and scraping herbivores, gall-forming insects and mites, and leaf-mining insects. We asked whether herbivory differs among different forest management regimes (unmanaged, uneven-aged managed, even-aged managed) and among age-classes within even-aged forests. We further tested for consistency of relationships between regions, strata and herbivore guilds. On average, almost 80 of beech leaves showed herbivory damage, and about 6 of leaf area was consumed. Chewing damage was most common, whereas leaf sucking and scraping damage were very rare. Damage was generally greater in the canopy than in the understorey, in particular for chewing and scraping damage, and the occurrence of mines. There was little difference in herbivory among differently managed forests and the effects of management on damage differed among regions, strata and damage types. Covariates such as wood volume, tree density and plant diversity weakly influenced herbivory, and effects differed between herbivory types. We conclude that despite of the relatively low number of species attacking beech; arthropod herbivory on beech is generally high. We further conclude that responses of herbivory to forest management are multifaceted and environmental factors such as forest structure variables affecting in particular microclimatic conditions are more likely to explain the variability in herbivory among beech forest plots.

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Natural regeneration is an ecological key-process that makes plant persistence possible and, consequently, it constitutes an essential element of sustainable forest management. In this respect, natural regeneration in even-aged stands of Pinus pinea L. located in the Spanish Northern Plateau has not always been successfully achieved despite over a century of pine nut-based management. As a result, natural regeneration has recently become a major concern for forest managers when we are living a moment of rationalization of investment in silviculture. The present dissertation is addressed to provide answers to forest managers on this topic through the development of an integral regeneration multistage model for P. pinea stands in the region. From this model, recommendations for natural regeneration-based silviculture can be derived under present and future climate scenarios. Also, the model structure makes it possible to detect the likely bottlenecks affecting the process. The integral model consists of five submodels corresponding to each of the subprocesses linking the stages involved in natural regeneration (seed production, seed dispersal, seed germination, seed predation and seedling survival). The outputs of the submodels represent the transitional probabilities between these stages as a function of climatic and stand variables, which in turn are representative of the ecological factors driving regeneration. At subprocess level, the findings of this dissertation should be interpreted as follows. The scheduling of the shelterwood system currently conducted over low density stands leads to situations of dispersal limitation since the initial stages of the regeneration period. Concerning predation, predator activity appears to be only limited by the occurrence of severe summer droughts and masting events, the summer resulting in a favourable period for seed survival. Out of this time interval, predators were found to almost totally deplete seed crops. Given that P. pinea dissemination occurs in summer (i.e. the safe period against predation), the likelihood of a seed to not be destroyed is conditional to germination occurrence prior to the intensification of predator activity. However, the optimal conditions for germination seldom take place, restraining emergence to few days during the fall. Thus, the window to reach the seedling stage is narrow. In addition, the seedling survival submodel predicts extremely high seedling mortality rates and therefore only some individuals from large cohorts will be able to persist. These facts, along with the strong climate-mediated masting habit exhibited by P. pinea, reveal that viii the overall probability of establishment is low. Given this background, current management –low final stand densities resulting from intense thinning and strict felling schedules– conditions the occurrence of enough favourable events to achieve natural regeneration during the current rotation time. Stochastic simulation and optimisation computed through the integral model confirm this circumstance, suggesting that more flexible and progressive regeneration fellings should be conducted. From an ecological standpoint, these results inform a reproductive strategy leading to uneven-aged stand structures, in full accordance with the medium shade-tolerant behaviour of the species. As a final remark, stochastic simulations performed under a climate-change scenario show that regeneration in the species will not be strongly hampered in the future. This resilient behaviour highlights the fundamental ecological role played by P. pinea in demanding areas where other tree species fail to persist.

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La Gestión Forestal Sostenible se define como “la administración y uso de los bosques y tierras forestales de forma e intensidad tales que mantengan su biodiversidad, productividad, capacidad de regeneración, vitalidad y su potencial para atender, ahora y en el futuro, las funciones ecológicas, económicas y sociales relevantes a escala local, nacional y global, y que no causan daño a otros ecosistemas” (MCPFE Conference, 1993). Dentro del proceso los procesos de planificación, en cualquier escala, es necesario establecer cuál será la situación a la que se quiere llegar mediante la gestión. Igualmente, será necesario conocer la situación actual, pues marcará la situación de partida y condicionará el tipo de actuaciones a realizar para alcanzar los objetivos fijados. Dado que, los Proyectos de Ordenación de Montes y sus respectivas revisiones son herramientas de planificación, durante la redacción de los mismos, será necesario establecer una serie de objetivos cuya consecución pueda verificarse de forma objetiva y disponer de una caracterización de la masa forestal que permita conocer la situación de partida. Esta tesis se centra en problemas prácticos, propios de una escala de planificación local o de Proyecto de Ordenación de Montes. El primer objetivo de la tesis es determinar distribuciones diamétricas y de alturas de referencia para masas regulares por bosquetes, empleando para ello el modelo conceptual propuesto por García-Abril et al., (1999) y datos procedentes de las Tablas de producción de Rojo y Montero (1996). Las distribuciones de referencia obtenidas permitirán guiar la gestión de masas irregulares y regulares por bosquetes. Ambos tipos de masas aparecen como una alternativa deseable en aquellos casos en los que se quiere potenciar la biodiversidad, la estabilidad, la multifuncionalidad del bosque y/o como alternativa productiva, especialmente indicada para la producción de madera de calidad. El segundo objetivo de la Tesis está relacionado con la necesidad de disponer de una caracterización adecuada de la masa forestal durante la redacción de los Proyectos de Ordenación de Montes y de sus respectivas revisiones. Con el fin de obtener estimaciones de variables forestales en distintas unidades territoriales de potencial interés para la Ordenación de Montes, así como medidas de la incertidumbre en asociada dichas estimaciones, se extienden ciertos resultados de la literatura de Estimación en Áreas Pequeñas. Mediante un caso de estudio, se demuestra el potencial de aplicación de estas técnicas en inventario forestales asistidos con información auxiliar procedente de sensores láser aerotransportados (ALS). Los casos de estudio se realizan empleando datos ALS similares a los recopilados en el marco del Plan Nacional de Ortofotografía Aérea (PNOA). Los resultados obtenidos muestran que es posible aumentar la eficiencia de los inventarios forestales tradicionales a escala de proyecto de Ordenación de Montes, mediante la aplicación de estimadores EBLUP (Empirical Best Linear Unbiased Predictor) con modelos a nivel de elemento poblacional e información auxiliar ALS similar a la recopilada por el PNOA. ABSTRACT According to MCPFE (1993) Sustainable Forest Management is “the stewardship and use of forests and forest lands in a way, and at a rate, that maintains their biodiversity, productivity, regeneration capacity, vitality and their potential to fulfill, now and in the future, relevant ecological, economic and social functions, at local, national, and global levels, and that does not cause damage to other ecosystems”. For forest management planning, at any scale, we must determine what situation is hoped to be achieved through management. It is also necessary to know the current situation, as this will mark the starting point and condition the type of actions to be performed in order to meet the desired objectives. Forest management at a local scale is no exception. This Thesis focuses on typical problems of forest management planning at a local scale. The first objective of this Thesis is to determine management objectives for group shelterwood management systems in terms of tree height and tree diameter reference distributions. For this purpose, the conceptual model proposed by García-Abril et al., (1999) is applied to the yield tables for Pinus sylvestris in Sierra de Guadrrama (Rojo y Montero, 1996). The resulting reference distributions will act as a guide in the management of forests treated under the group shelterwood management systems or as an approximated reference for the management of uneven aged forests. Both types of management systems are desirable in those cases where forest biodiversity, stability and multifunctionality are pursued goals. These management systems are also recommended as alternatives for the production of high quality wood. The second objective focuses on the need to adequately characterize the forest during the decision process that leads to local management. In order to obtain estimates of forest variables for different management units of potential interest for forest planning, as well as the associated measures of uncertainty in these estimates, certain results from Small Area Estimation Literature are extended to accommodate for the need of estimates and reliability measures in very small subpopulations containing a reduced number of pixels. A case study shows the potential of Small Area Estimation (SAE) techniques in forest inventories assisted with remotely sensed auxiliary information. The influence of the laser pulse density in the quality of estimates in different aggregation levels is analyzed. This study considers low laser pulse densities (0.5 returns/m2) similar to, those provided by large-scale Airborne Laser Scanner (ALS) surveys, such as the one conducted by the Spanish National Geographic Institute for about 80% of the Spanish territory. The results obtained show that it is possible to improve the efficiency of traditional forest inventories at local scale using EBLUP (Empirical Best Linear Unbiased Predictor) estimators based on unit level models and low density ALS auxiliary information.

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黄龙世界自然遗产地岷江冷杉林(Abies faxoniana)生境类型多样,群落结构复杂,群落植物种类组成多样性丰富。揭示不同生境的生物多样性及其差异是认识生物多样性格局、形成及维持机制的前提和进行多样性保育的基础。本文采用样方法对黄龙钙化滩生境、阴坡非钙化生境及半阳坡非钙化生境的岷江冷杉原始林植物群落结构及植物多样性进行了研究。结果表明: 黄龙岷江冷杉林具有明显的复层异龄结构,垂直结构明显,乔木、灌木、草本、苔藓层次分明。共发现高等植物386 种,其中维管植物46 科103 属163 种,苔藓植38 科83 属物223 种。各层片结构及物种组成如下: (1)钙化滩生境、阴坡非钙化生境、半阳坡非钙化生境分别发现乔木18 种、13种、8 种。乔木层均可分为两个亚层,第一亚层优势种均为岷江冷杉,第二亚层主要为岷江冷杉异龄树或其它大高位芽物种。钙化滩生境第一亚层除优势种岷江冷杉外混生有巴山冷杉(Abies fargesii)、粗枝云杉(Picea asperata)以及阔叶树种白桦(Betula platyphylla)等,第二亚层主要为岷江冷杉异龄树;阴坡非钙化生境第一亚层除优势种岷江冷杉外间有巴山冷杉和白桦,第二亚层物种主要为川滇长尾槭(Acer caudatum var. prattii);半阳坡非钙化生境第一亚层除优势种岷江冷杉外混生有巴山冷杉,第二亚层主要为岷江冷杉异龄树。依乔木层优势种的差异,钙化滩生境及半阳坡非钙化生境为岷江冷杉纯林,阴坡非钙化生境为岷江冷杉-川滇长尾槭混交林。不同生境乔木层郁闭度、乔木密度、树高结构、直径结构均存在差异。 (2)钙化滩生境发现灌木41 种,平均盖度为18.49±1.72(%),平均高度为52.12±4.45(cm),优势种为直穗小檗(Berberis dasystachya);阴坡非钙化生境发现灌木30 种,平均盖度为29.33±2.56 (%),平均高度为119.55±8.01 (cm),优势种为箭竹 (Fargesia spathacea) 、唐古特忍冬(Lonicera tangutica) 和袋花忍冬(Lonicera saccata);半阳坡非钙化生境发现灌木29 种,平均盖度为31.35±1.93 (%),平均高度为107.55±4.24 (cm),优势种为箭竹(Fargesia spathacea)。不同生境灌木层结构和物种组成多样性差异显著,钙化滩生境的灌木盖度、高度总体上较非钙化的坡地生境低, 钙化滩生境灌木以小型叶的落叶灌木为主,沟两侧非钙化的坡地生境上则发育了丰富箭竹。 (3)钙化滩生境发现草本46 种,平均盖度为7.18±0.79 (%),平均高度为5.04±0.26(cm),以山酢浆草(Oxalis griffithii)为优势种;阴坡非钙化生境发现草本物种71 种,平均盖度达29.04±2.31(%),平均高度为9.08±0.52(cm),以钝叶楼梯草(Elatostema obtusum)、山酢浆草为优势种;半阳坡非钙化生境草本物种50 种,平均盖度为以8.79±0.82(%),平均高度为7.67±0.43 (cm),以扇叶铁线蕨(Adiantum flabellulatum)、双花堇菜(Viola biflora)、华中蛾眉蕨(Lunathyrium shennongense)、山酢浆草为优势种。阴坡非钙化生境草本层片发育良好,多样性最为丰富,盖度和物种丰富度均显著高于钙化滩生境和半阳坡非钙化生境。 (4)钙化滩生境发现苔藓物种140 种,平均盖度达84.25±1.30 (%),以仰叶星塔藓(Hylocomiastrum umbratum) 等大型藓类为优势种;阴坡非钙化生境发现苔藓物种115 种,平均盖度为79.29±1.64 (%),以刺叶提灯藓(Mnium spinosum)、大羽藓(Thuidium cymbifolium)、毛尖燕尾藓(Bryhnia trichomitra)等个体较小的物种为优势种;半阳坡非钙化生境发现苔藓物种91 种,平均盖度为60.64±1.93 (%),也以刺叶提灯藓为优势种。 (5)钙化滩生境、阴坡非钙化生境、半阳坡非钙化生境的物种数分别为234 种、221 种、175 种。乔木层的Shannon-Wiener 指数分别为0.75 ±0.12、1.87±0.12、1.78±0.07(灌木层,0.44±0.08、1.71± 0.15、2.49±0.06;草本层,0.33±0.13、1.31±0.15 、2.15±0.08; 苔藓层1.30±0.11、2.08±0.04、1.73±0.11,);Pielou 均匀度指数分别为0.45±0.05、0.29±0.06、0.28±0.08(灌木层,0.75±0.03、0.68±0.05、0.52±0.06;草本层,0.68±0.02、0.77±0.02、0.74±0.02;苔藓层,0.40±0.03、0.63±0.02、0.52±0.03);Simpson's 优势度指数分别为0.63±0.06、0.78±0.04、0.83±0.07(灌木层,0.21±0.03、0.28±0.05、0.45±0.06;草本层,0.25±0.02、0.12±0.01、0.17±0.01;苔藓层,0.45±0.04、0.18±0.01、0.31±0.04)。三种生境间乔木层、草本层的Sorenson 群落相似性系数较低, 灌木层、苔藓层的的Sorenson 群落相似性系数较高。 综上所述,黄龙岷江冷杉林的群落结构、植物多样性在三种生境间存在差异性,这将意味着我们在进行黄龙世界自然遗产地的森林经营管理时要较多地关注岷江冷山林群落在不同生境中的差异性。 There were multiplex habitat types, complicated community structure and abundant species composition in the Huanglong World Natural Heritage Site. Uncovering the differences of biodiversity among different habitats was a precondition to understand the distribution, formation and sustaining mechanism of the biodiversity, and the foundation of biodiversity conservation. In the present study, using plenty of quadrants, we investigated the community structure and the biodiversity of the primitive Abies faxoniana forest in different habitats (travertine bottomland, semi-sunny-slope non-calcified habitat and shady-slope non-calcified habitat) in the Huanglong World Natural Heritage Site. The main results are as follows: All the primitive Abies faxoniana forests in the three habitats were uneven-aged with obvious vertical structure including tree layer, shrub layer, herb layer and bryophyte layer. A total of 386 higher plants including 163 vascular plant species (103 generic, 46 families) and 223 bryophyte species (83 generic, 38 families) were investigated. The structure and species composition of each layer are as follows: (1) There were 18, 13 and 8 tree species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. The tree layers in all habitats can be divided into two clear sub-layers. The upper tree layers were dominated by Abies faxoniana, and the lower tree layers were dominated by uneven-aged Abies faxoniana or other phanerophytes species. There were Abies fargesii , Picea asperata and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in travertine bottomland, and the lower tree layers were dominated by uneven-aged Abies faxoniana; There were Abies fargesii and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in shady-slope non-calcified habitat, and the lower tree layers were dominated by Acer caudatum var. prattii; There was Abies fargesii besides the dominated species (Abies faxoniana) in the upper tree layer semi-sunny-slope non-calcified habitat, and the lower tree layers were dominated by uneven-aged Abies faxoniana. According to composition percentage of dominate species in tree layer, both the forest in travertine bottomland and in semi-sunny-slope non-calcified habitat could be ranked as pure forest, and the forest in shady-slope non-calcified habitat could be ranked as mingled forest. There were significant differences in crown density, plant density, height structure and diameter structure among the three habitats. (2) A total of 41 shrub species (average coverage 18.49±1.72%; average height 52.12±4.45 ㎝)were found in travertine bottomland, and the dominate species was Berberis dasystachya; A total of 30 shrub species (average coverage 29.33±2.56 %;average height 119.55±8.01 ㎝)were found in shady-slope non-calcified habitat, and the dominate species was Fargesia spathacea, Lonicera tangutica and Lonicera saccata. A total of 29 shrub species (average coverage 31.35±1.93%; average height 107.55±4.24 ㎝) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Fargesia spathacea. There were significant differences in structure and species diversity of the shrub layers among the three habitats. The coverage and height of shrub had lower value in travertine bottomland than in two non-calcified habitats. Moreover, travertine bottomland was dominated by deciduous shrub species with microphyll and non-calcified habitats developed abundant Fargesia spathacea species. (3) A total of 46 herb species (average coverage 7.18±0.79%;average height 5.04±0.26 ㎝)were found in travertine bottomland, and the dominate species was Oxalis griffithii; A total of 71 herb species (average coverage 29.04±2.31%;average height 9.08±0.52 ㎝)were found in shady-slope non-calcified habitat, and the dominate species was Elatostema obtusum and Oxalis griffithii. A total of 50 herb species (average coverage 8.79±0.82%;average height 7.67±0.43 ㎝) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Adiantum flabellulatum, Viola biflora, Lunathyrium shennongense and Oxalis griffithii. Herb layers developed well in shady-slope non-calcified habitat and had the higher species richness and coverage than travertine bottomland and semi-sunny-slope non-calcified habitat. (4) A total of 140 bryophyte species (average coverage 84.25±1.30%)were found in travertine bottomland, and the dominate species was big bryophyte species such as Hylocomiastrum umbratum and so on; A total of 115 bryophyte species (average coverage 79.29±1.64%)were found in shady-slope non-calcified habitat, and the dominate species was small bryophyte species such as Mnium spinosum, Thuidium cymbifolium, Bryhnia trichomitra and so on. A total of 91 bryophyte species (average coverage 60.64±1.93%) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Mnium spinosum. (5) There were 234, 221 and 175 plant species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. Shannon-Wiener index of the tree layer was 0.75 ±0.12, 1.87±0.12 and 1.78±0.07 (the shrub layer, 0.44±0.08, 1.71± 0.15 and 2.49±0.06; the herb layer, 0.33±0.13, 1.31±0.15 and 2.15±0.08; the bryophyte layer, 1.30±0.11, 2.08±0.04 and 1.73±0.11.) for the three habitats, respectively; Pielou index of the tree layer was 0.45±0.05, 0.29±0.06 and 0.28±0.08 (the shrub layer, 0.75±0.03, 0.68±0.05 and 0.52±0.06; the herb layer, 0.68±0.02, 0.77±0.02 and 0.74±0.02; the bryophyte layer, 0.40±0.03, 0.63±0.02 and 0.52±0.03.) for the three habitats, respectively. Simpson's index of the tree layer was 0.63±0.06, 0.78±0.04 and 0.83±0.07 (the shrub layer, 0.21±0.03、0.28±0.05、0.45±0.06; the herb layer, 0.25±0.02, 0.12±0.01 and 0.17±0.01; the bryophyte layer, 0.45±0.04, 0.18±0.01 and 0.31±0.04.) for the three habitats, respectively. There were low Sorenson index both in the tree layer and in the herb layer among the three habitats, whereas, high Sorenson index occurred both in the shrub layer and in the bryophyte layer. To sum up, there were differences both in community structure and plant diversity among the three different habitats, which means that we should pay more attention to habitats heterogeneities of the primitive Abies faxoniana forest when we take action to manage the forest in the Huanglong World Natural Heritage Site.

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Green-tree retention under the conceptual framework of ecological forestry has the potential to provide both biomass feedstock for industry and maintain quality wildlife habitat. I examined the effects of retained canopy trees as biological legacies (“legacy trees”) in aspen (Populus spp.) forests on above-ground live woody biomass, understory plant floristic quality, and bird diversity. Additionally, I evaluated habitat quality for a high conservation priority species, the Golden-winged Warbler (Vermivora chrysoptera). I selected 27 aspen-dominated forest stands in northern Wisconsin with nine stands in each of three legacy tree retention treatments (conifer retention, hardwood retention, and clearcuts or no retention) across a chronosequence (4-36 years post-harvest). Conifer retention stands had greater legacy tree and all tree species biomass but lower regenerating tree biomass than clearcuts. Coniferous but not hardwood legacy trees appeared to suppress regenerating tree biomass. I evaluated the floristic quality of the understory plant assemblage by estimating the mean coefficient of conservatism (C). Mean C was lower in young stands than in middle-age or old stands; there was a marginally significant (p=0.058) interaction effect between legacy tree retention treatment and stand age. Late-seral plant species were positively associated with stand age and legacy tree diameter or age revealing an important relationship between legacy tree retention and stand development. Bird species richness was greatest in stands with hardwood retention particularly early in stand development. Six conservation priority bird species were indicators of legacy tree retention or clearcuts. Retention of legacy trees in aspen stands provided higher quality nest habitat for the Golden-winged Warbler than clearcuts based on high pairing success and nesting activity. Retention of hardwoods, particularly northern red oak (Quercus rubra), yielded the most consistent positive effects in this study with the highest bird species richness and the highest quality habitat for the Golden-winged Warbler. This treatment maintained stand biomass comparable to clearcuts and did not suppress regenerating tree biomass. In conclusion, legacy tree retention can enhance even-aged management techniques to produce a win-win scenario for the conservation of declining bird species and late-seral understory plants and for production of woody biomass feedstock from naturally regenerating aspen forests.

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A joint analysis of data on the anomalous magnetic field, seismicity, and structures of the Hess deep basalts have allowed to specify propagation of the spreading zone and to correct position of the neovolcanic zone. A precise petrogeochemical analysis of various types of basalts composing the uneven-aged oceanic crust of the basin showed that magmatics of the neovolcanic zone are related to the primitive type in contrast to rift boards of differential basalts. A model of the deep structure of the Galapagos rift in the area of the western Hess Deep has been suggested.

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La fase de establecimiento del regenerado es un proceso crítico para el desarrollo posterior de la masa tanto por las elevadas tasas de mortalidad que habitualmente lleva asociadas, como por proporcionar el material de partida del que van a disponer las fases subsiguientes. Las restricciones a la germinación y establecimiento de la regeneración del pino silvestre varían enormemente entre las distintas regiones de su extensa área de distribución geográfica. La región Mediterránea constituye un hábitat marginal de la especie en el que las condiciones ecológicas son muy diferentes a las del grueso de su área de distribución. Frente a otras limitaciones (frío, luz, encharcamiento…), en el entorno mediterráneo la tasa de mortalidad parece estar asociada a las condiciones micrometeorológicas del período estival - particularmente, a la sequía -, así como a la presencia excesiva de ganado o ungulados silvestres. No obstante, la mayoría de la información disponible sobre el proceso de regeneración de la especie procede del centro y norte de Europa, por lo que no es de aplicación directa en nuestra región, en la que los estudios de este tipo son mucho más escasos. El presente trabajo pretende contribuir a paliar esta relativa escasez a través del estudio del proceso de regeneración natural en el monte “Cabeza de Hierro”, masa irregular por bosquetes de pino silvestre, paradigma de gestión sostenible y uso múltiple. En este entorno, se pretende caracterizar y cuantificar tanto el proceso de germinación y supervivencia de la especie como la influencia de la cobertura vegetal (estratos arbóreo, arbustivo y herbáceo, y capa de restos vegetales) en su desarrollo. Se persigue así mismo analizar el efecto de la compactación del suelo sobre la persistencia de la masa y contrastar y comparar la eficacia de dos tratamientos edáficos de ayuda a la regeneración: escarificado y decapado+acaballonado. Con este fin se han planteado dos diseños experimentales consistentes en sendas redes de muestreo (Red de Muestreo I o RM I y Red de Muestreo II o RM II) integradas, respectivamente, por 192 y 24 parcelas de 1,5x1,5 m ubicadas bajo distintas condiciones de cobertura vegetal. Sobre una parte de estas parcelas (1/4 en la Red de Muestreo I; 1/2 en la Red de Muestreo II) se han aplicado tratamientos de ayuda a la regeneración (RM I: escarificado; RM II: decapado+acaballonado) y, tras llevar a cabo siembras controladas al inicio del período vegetativo, se han practicado controles periódicos de germinación y supervivencia durante uno (RM II) y tres años consecutivos (RM I). Se han realizado así mismo mediciones complementarias de variables micrometeorológicas, espesura, recubrimiento superficial del suelo y compactación. Los resultados obtenidos a partir de las experiencias realizadas en el monte objeto de estudio permiten concluir que, en relación con el proceso de regeneración natural de la especie en este tipo masa y entorno: 1) la regeneración del pino silvestre durante el primer período vegetativo presenta una tasa de éxito muy baja (1,4% de los sembrados), provocada por una elevada mortalidad durante el primer período estival (>92%) subsiguiente a una germinación de en torno al 17% de las semillas viables que llegan al suelo; 2) la mortalidad sigue siendo elevada hasta el tercer período vegetativo, en que comienza a reducirse significativamente hasta alcanzar el 45%; 3) la cobertura vegetal influye significativamente tanto en el proceso de germinación como en el de supervivencia, aunque ambos procesos presentan una baja correlación linear que pone de manifiesto que los lugares idóneos para la germinación no siempre son los más adecuados para la supervivencia; 4) la escarificación del suelo mejora las tasas iniciales de germinación y supervivencia, pero empeora la tasa de supervivencia posterior (años 2 y 3), por lo que su efecto a medio plazo no resulta significativo; 5) el decapado+acaballonado presenta mejores resultados que el escarificado durante el primer verano, aunque sólo resulta efectivo en condiciones intermedias de espesura de masa; 6) la compactación edáfica no resulta limitante para la productividad ni la persistencia de la masa considerada. ABSTRACT Seedling establishment is critical for later stand progress because it involves high mortality rates and the surviving saplings constitute the starting material for all the subsequent stages. Restrictions for Scots pine germination and seedling survival may vary greatly across its geographical range, as it is widely distributed within north latitudes. Mediterranean region is a marginal sector within this species range and its ecological conditions differ greatly from those of the bulk of the area. Mortality rates in Mediterranean environments seem to be related to summer weather (mainly drought) and high livestock stocking rather than to cold, light or flooding. Most available information on scots pine regeneration process comes from north European experiences and is not transferable to Spanish forests, whereas studies on Mediterranean region are much scarcer. The present work aims at broadening Scots pine regeneration knowledge within Mediterranean region by analyzing its establishment process in the “Cabeza de Hierro” forest: a Scots pine uneven-aged forest at blocklevel scale, exemplary managed for multi-services purpose. Germination and surviving processes are to be characterized and quantified as to vegetation cover both in trees, shrubs, grass and litter strata. Soil compaction effects on forest sustainability are also assessed and the efficacy of some site preparation techniques on regeneration success is tested and compared (scarification vs. scalping+mounding). Two sampling networks comprising respectively 198 (SN I) and 24 plots (SN II) of 1.5x1.5m have been established over a wide range of vegetal cover conditions within the forest. Soil preparation techniques have been applied only to some of the sampling points; namely, 1 out of 4 plots have been scarified within Sampling Network I , while 1 out of 2 plots have been object of scalping & mounding within Sampling Network II. After localized sowing prior to growing season, germination and surviving have been periodically sampled for either one (SN II) or three years (SN I). Supplementary measures for micrometeorological variables, stand density, ground vegetal cover and compaction have also been carried out. Results obtained for the studied forest lead to the following insights regarding Scots pine natural regeneration process within this sort of forest and environment: 1) seedling establishment success rate is quite low (0,15% of sowing seeds), due to high mortality during the first summer (>92%), following a prior 17% rate of germination over viable seeds reaching the soil; 2) mortality rate remains high until the third year after emergence and then decreases to the 50% of surviving; 3) although vegetal cover significantly affects both seedling germination and survival, lineal correlation between those two processes is rather low, which may indicate that places fit for emergence are not necessarily suitable for summer surviving; 4) soil scarification improves both germination and survival during the first growing season, but it is associated to higher mortality rates during the next two years; hence it has no significant medium term effect; 5) scalping & mounding treatment is more effective than scarification concerning establishment improving during the first summer; but its effects are only significant under intermediate stand density levels; 6) soil compaction does not restrict either forest productivity or persistence, despite the area’s long history of high livestock stocking rates and mechanized logging.

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BACKGROUND: A comparison of the management of medicines by the older-aged living in freehold (fully owned) and rental homes in retirement villages has suggested that the older-aged living in rental, but not freehold, retirement villages may require help to manage their medicines. OBJECTIVE: The objective of this study was to investigate the management of medicines by the older-aged living independently in a leasehold (partly owned) home in retirement village to determine whether they also need help in managing their medicines. METHOD: Semi-structured interviews were conducted with 22 older-aged residents living in a leasehold retirement village. MAIN OUTCOME MEASURE: The main outcome measure was the perception of present and ongoing adherence. RESULTS: Amongst participants in the leasehold retirement village, with an average age of 82.9 years, the perceptions of present and ongoing adherence indicated that only 55 % of older-aged participants were adherent at the time of the study, and not likely to have problems with adherence within the next 6-12 months. Participants from the leasehold retirement village had a good understanding of 58 % of their illnesses. A mean of 9.8 medicines per person were prescribed. Cardiovascular medicines were the most commonly prescribed at 86 %. CONCLUSION: The older-aged living in leasehold retirement villages may require extra assistance/resources to manage their medicines.

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Pain is common in residential aged care facilities (RACFs). In 2005, the Australian Pain Society developed 27 recommendations for good practice in the identification, assessment, and management of pain in these settings. This study aimed to address implementation of the standards and evaluate outcomes. Five facilities in Australia participated in a comprehensive evaluation of RACF pain practice and outcomes. Pre-existing pain management practices were compared with the 27 recommendations, before an evidence-based pain management program was introduced that included training and education for staff and revised in-house pain-management procedures. Post-implementation audits evaluated the program's success. Aged care staff teams also were assessed on their reports of self-efficacy in pain management. The results show that before the implementation program, the RACFs demonstrated full compliance on 6 to 12 standards. By the project's completion, RACFs demonstrated full compliance with 10 to 23 standards and major improvements toward compliance in the remaining standards. After implementation, the staff also reported better understanding of the standards (p < .001) or of facility pain management guidelines (p < .001), increased confidence in therapies for pain management (p < .001), and increased confidence in their training to assess pain (p < .001) and recognize pain in residents with dementia who are nonverbal (p = .003). The results show that improved evidence-based practice in RACFs can be achieved with appropriate training and education. Investing resources in the aged care workforce via this implementation program has shown improvements in staff self-efficacy and practice.